Various devices and compositions have been employed to condition fibers, fabrics and laundry. Such conditioning may be effected with any of various suitable agents to improve a wide variety of properties of the materials treated. Generally, the most important conditioning effected is softening, especially with respect to cottons which have been laundered in aqueous solutions of heavy duty synthetic organic detergents. Also, and of increasing importance with the growing use of synthetic fabrics, treatment of such fabrics and laundry incorporating them has been desirable to diminish objectionable tendencies of such materials to become electrostatically charged, whereby they cling together or adhere closely and objectionably to various other surfaces. Of course, other conditioning may also be effected, such as making the treated articles antibacterial, soil-repellant, antifungal, perfumed, brightened, sized or lubricated. With respect to the various above treatments, especially with respect to softening fabrics and making them antistatic, the principal mechanisms employed in the past have relied on the substantivity of the treating material to the fabrics being treated. Thus, a treating chemical, dissolved in the last rinse, becomes tightly held by the fabric and is not removed after discharge of the rinse water and subsequent drying. Recently, such softening and/or antistatic agents have been applied to materials in conjunction with the drying operation. Thus, in U.S. Pat. No. 3,442,692, it is taught that various cationic conditioning agents can be used to impregnate flexible substrate materials, such as paper, cloth or sponge, and can be vaporized from these as they are tumbled during a drying operation, so that they may be sorbed by the moving laundry present in the dryer. Other researchers in the laboratories of the assignee of the present application have discovered various other compositions, articles, apparatuses and methods for treating fabrics and laundry in an automatic laundry dryer or similar machine and effecting improved conditioning thereof. Some of those improvements have been described in patent applications on such subjects which are so assigned and are filed on the same day as the present application.
Although such methods represent important improvements in the softening of laundry, utilizing a drying step which is employed anyway, the present apparatus and method represent further advances in this art, whereby good softening is obtained and the softening articles are very easy to use, requiring a minimum of effort on the part of the housewife and thereby greatly improving their consumer acceptances.